This invention relates to an aluminosilicate zeolitic material identified as UZM-16. The material can be dealuminated to form UZM-16HS providing materials with different acidity, porosity, and ion-exchange properties. UZM-16 and UZM-16HS are useful in hydrocarbon conversion processes.
Zeolites are crystalline aluminosilicate compositions which are microporous and which are formed from comer sharing AlO2 and SiO2 tetrahedra. Numerous zeolites, both naturally occurring and synthetically prepared are used in various industrial processes. Synthetic zeolites are prepared via hydrothermal synthesis employing suitable sources of Si, Al, as well as structure directing agents such as alkali metals, alkaline earth metals, amines, or organoammonium cations. The structure directing agents reside in the pores of the zeolite and are largely responsible for the particular structure that is ultimately formed. These species balance the framework charge associated with aluminum and can also serve as space fillers. Zeolites are characterized by having pore openings of uniform dimensions, having a significant ion exchange capacity, and being capable of reversibly desorbing an adsorbed phase which is dispersed throughout the internal voids of the crystal without significantly displacing any atoms which make up the permanent zeolite crystal structure. Zeolites can be used as catalysts for hydrocarbon conversions, which can take place on outside surfaces as well as on internal surfaces within the pore.
A synthetic zeolite designated Zeolite T has been prepared in the Na, K system and disclosed by Breck and Acara in U.S. Pat. No. 2,950,952. A subsequent crystallographic investigation employing electron diffraction (J. M. Bennett and J. A. Gard, Nature, 214, 1005 (1967)) provided distinctions and established the uniqueness of the offretite and erionite frameworks and classified Zeolite T as an intergrowth of the two structures. A synthetic zeolite with the offretite structure free of erionite intergrowth was prepared in the Na, K, TMA and K, TMA systems (R. Aiello and R. Barrer, J. Chem. Soc. (A), 1470, (1970)). Rubin and Rosinsky were able to prepare a material related to erionite in the benzyltrimethylammonium (BzTMA), Na, K system (U.S. Pat. No. 3,699,139). Working in the same system, an offretite sample free of x-ray diffraction lines due to erionite were prepared (M. L. Occelli, R. A. Innes, S. S. Pollack, and J. V. Sanders, Zeolites, 7, 265 (1987)). An electron diffraction study of offretite, erionite, and offretite-erionite species resulting from syntheses that cover six organic template systems, including BzTMA, characterize the many types of faults that occur in this system (J. V Sanders, M. L. Occelli, R. A. Innes, and S. S. Pollack, Studies in Surface Science and Catalysis, Ed. Y. Murakami, A. Iijima, and J. W. Ward, Elsevier, New York, 28, 429, (1986)).
Applicants have now prepared a zeolite designated UZM-16 which has some similarities to offretite, but has sufficient differences rendering it a unique new structure. UZM-16 can be prepared in the benzyltrimethylammonium (BzTMA) system with a small amount of additional potassium. The x-ray diffraction pattern is similar to offretite, lacking the lines associated with erionite, but also includes a broad line in the pattern centered at about d=21.5 xc3x85, that includes unresolved peaks extending from d=18 xc3x85 to about 27 xc3x85. This feature is observed in the electron diffraction patterns of the crystals and as fringes in high resolution lattice images. In addition, a unique periodicity observed in the a-b plane that is not known for offretite and erionite is observed in the electron diffraction patterns of UZM-16. UZM-16 has more mesoporous character than offretite.
This invention relates to a new family of zeolites, a process for preparing the zeolites and processes using the zeolites. Accordingly, one embodiment of the invention is a microporous crystalline zeolite having a composition in the as-synthesized form in terms of mole ratios of the elements given by                               M          m                      n            +                          ⁢                  xe2x80x83                ⁢                  R          r                      p            +                          ⁢                  xe2x80x83                ⁢                  Al                      (                          1              -              x                        )                          ⁢                  E          x                ⁢                  xe2x80x83                ⁢                  Si          y                ⁢                  xe2x80x83                ⁢                  O          z                                    (        1        )            
where M is at least one exchangeable cation selected from the group consisting of alkali and alkaline earth metals, xe2x80x9cmxe2x80x9d is the mole ratio of M to (Al+E) and varies from 0 to about 0.75, R is benzyltrimethylammonium (BzTMA) cation or a combination of BzTMA and at least one quaternary ammonium cation, xe2x80x9crxe2x80x9d is the mole ratio of R to (Al+E) and has a value of about 0.25 to about 5.0, E is an element selected from the group consisting of Ga, Fe, In, Cr, B, and mixtures thereof xe2x80x9cxxe2x80x9d is the mole fraction of E and varies from 0 to about 1.0, xe2x80x9cnxe2x80x9d is the weighted average valence of M and has a value of about +1 to about +2, xe2x80x9cpxe2x80x9d is the weighted average valence of R and has a value of +1 to about +2, xe2x80x9cyxe2x80x9d is the mole ratio of Si to (Al+E) and has a value from greater than 3 to about 25 and xe2x80x9czxe2x80x9d is the mole ratio of O to (Al+E) and has a value determined by the equation:
z=(mxc2x7n+rxc2x7p+3+4xc2x7y)/2;
the zeolite characterized in that it has an x-ray diffraction pattern having at least the d-spacings and relative intensities set forth in Table A.
Another embodiment of the invention is a process for preparing the above-described zeolites which comprises forming a reaction mixture containing reactive sources of M, R, Al, Si and optionally E and heating the reaction mixture at a temperature of about 80xc2x0 C. to about 160xc2x0 C., the reaction mixture having a composition expressed in terms of mole ratios of the oxides of:
aM2/nO:bR2/pO:(1xe2x88x92c)Al2O3:cE2O3:dSiO2:eH2O
where xe2x80x9caxe2x80x9d has a value of 0 to about 5, xe2x80x9cbxe2x80x9d has a value of about 1 to about 120, xe2x80x9ccxe2x80x9d has a value of 0 to about 1.0, xe2x80x9cdxe2x80x9d has a value of about 5 to about 100, and xe2x80x9cexe2x80x9d has a value of about 50 to about 15000.
A further embodiment of the invention is a microporous crystalline zeolite having an empirical composition on an anhydrous basis in terms of mole ratios of the elements of:             M1      n              n        +              ⁢          xe2x80x83        ⁢          Al              (                  1          -          x                )              ⁢          xe2x80x83        ⁢          E      x        ⁢          xe2x80x83        ⁢          Si              y        xe2x80x2              ⁢          xe2x80x83        ⁢          O              z        xe2x80x3              ⁢      xe2x80x83  
where M1 is at least one exchangeable cation selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, ammonium ion, hydrogen ion and mixtures thereof, a is the mole ratio of M1 to (Al+E) and varies from about 0.01 to about 50, E is an element selected from the group consisting of gallium, iron, boron, chromium, indium and mixtures thereof, x is the mole fraction of E and varies from 0 to about 1.0, n is the weighted average valence of M1 and has a value of about +1 to about +3, yxe2x80x2 is the mole ratio of Si to (Al+E) and is greater than about 3 and zxe2x80x3 is the mole ratio of O to (Al+E) and has a value determined by the equation:
zxe2x80x3=(axc2x7n+3+4xc2x7yxe2x80x2)/2;
the zeolite characterized in that it has an x-ray diffraction pattern having at least the d-spacings and relative intensities set forth in Table B.
Another embodiment of the invention is a process for preparing a modified microporous crystalline zeolite having an empirical composition on an anhydrous basis in terms of mole ratios of the elements of:             M1      n              n        +              ⁢          xe2x80x83        ⁢          Al              (                  1          -          x                )              ⁢          xe2x80x83        ⁢          E      x        ⁢          xe2x80x83        ⁢          Si              y        xe2x80x2              ⁢          xe2x80x83        ⁢          O      z        ⁢      xe2x80x83  
where M1 is at least one exchangeable cation selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, ammonium ion, hydrogen ion and mixtures thereof, a is the mole ratio of M1 to (Al+E) and varies from about 0.01 to about 50, E is an element selected from the group consisting of gallium, iron, boron, chromium, indium and mixtures thereof, x is the mole fraction of E and varies from 0 to about 1.0, n is the weighted average valence of M1 and has a value of about +1 to about +3, yxe2x80x2 is the mole ratio of Si to (Al+E) and is greater than about 3 and zxe2x80x3 is the mole ratio of O to (Al+E) and has a value determined by the equation:
zxe2x80x3=(axc2x7n+3+4xc2x7yxe2x80x2)/2
the process comprising treating a starting zeolite at treating conditions thereby removing at least a portion of the framework aluminum and optionally inserting silicon into the framework to provide the modified zeolite; the starting zeolite having an empirical formula on an anhydrous basis of:       M          m      xe2x80x2              n      +        ⁢      xe2x80x83    ⁢      R          r      xe2x80x2              p      +        ⁢      xe2x80x83    ⁢      Al          (              1        -        x            )        ⁢      xe2x80x83    ⁢      E    x    ⁢      xe2x80x83    ⁢      Si          y      xe2x80x2        ⁢      xe2x80x83    ⁢      O          z      xe2x80x2      
where Mxe2x80x2 is an exchangeable cation selected from the group consisting of ammonium ion, hydrogen ion, alkali metals, alkaline earth metals, rare earth metals and mixtures thereof, n is the weighted average valence of Mxe2x80x2 and varies from +1 to about +3, mxe2x80x2 is the mole ratio of Mxe2x80x2 to (Al+E) and varies from 0 to about 5.75, R is benzyltrimethylammonium (BzTMA) cation or a combination of BzTMA and an organoammonium cation selected from the group consisting of protonated amines, protonated diamines, protonated alkanolamines, quaternary ammonium ions, diquarternary ammonium ions, quaternized alkanolammonium ions and mixtures thereof, p is the average weighted valence of the organic cation and varies from about +1 to about +2, rxe2x80x2 is the mole ratio of R to (Al+E) and varies from 0 to about 5.75, rxe2x80x2+mxe2x80x2 greater than 0, yxe2x80x2 is the ratio of Si to (Al+E) and varies from greater than 3 to about 25 and zxe2x80x2 is the mole ratio of O to (Al+E) and has a value given by the equation:
xe2x80x83zxe2x80x2=(mxe2x80x2xc2x7n+rxe2x80x2xc2x7p+3+4xc2x7yxe2x80x2)/2.
Yet another embodiment of the invention is a hydrocarbon conversion process using any of the above-described zeolites. More specifically the hydrocarbon conversion process is conversion of cyclic compounds to non-cyclic compounds, i.e. linear or branched compounds.
These and other objects and embodiments will become more apparent after the following detailed description of the invention.